DIAGNOSIS

There are semiologic methods to verify the localization of pain in the patient. Nevertheless, the x-ray exam is the only diagnostic method for hip displasia which has worldwide acceptance.

The minimum age for official hip diagnosis in German shepherds and similar sized breeds is 1 year.
In giant breeds it is at the age of 18 months . At this age skeleton development is considered to have been completed.
Exploratory x-rays taken before the first year of age, are of utmost relevance to decide on the animal future, either as a structural dog, used in breeding stocks or as labour dogs, which will have to perform greater efforts. Without a good skeleton conformation the latter will not be able to endure the required effort.

Differential diagnosis is made concerning pathologies which present a similar pattern but mainly with lumber-sacrum compression, which is the most frequent.

CONDITIONS TO TAKE AN OFFICIAL X-RAY

•  Identification of the sample, either through tattoo or microchip.
•  Identification of the x-ray. It must show in an indelible way the same tattoo number or the microchip code in the x-ray.

Besides, the x-ray must also show:

•  The pedigree number of the dog.
•  The birth date.
•  The x-ray date.
•  Name of the veterinarian who takes the x-ray.

The x-ray must be of 30 x 40 cm.

The image must be of good quality. For this purpose x-ray equipment need to have appropriate power in order to obtain well-defined images with good contrast.
To obtain a good image implies not only x-ray equipment but also quality of the chassis , screens, bucky and of the developing techniques.

Identification of the
x-ray

Technical quality

An x-ray is considered to be of good technical quality and of diagnostic value, when the dorsal acetabular rim can be seen through the head of the femur and the osseous structure.
The animal must be adequately sedated so as to be allowed to place it in the correct position.

The “I” position with stretched posterior limbs and the animal in ventral-dorsal position. It is correctly positioned when the pelvis is shown symmetrically . with the ilium wings are perfectly equal. The foramina obturata are symmetric and of the same size. Femurs are stretched and parallel to each other and to the table. An internal rotation of the femurs must be performed so that the patellas are located in the centre of the femoral condyles and at sesamoids height "I" Position - stretched posterior limbs (HAN u. HURD, 1994)

"I" Position - stretched posterior limbs

The “II” position or “of frog” is taken with the animal in dorsal position with folded hind legs and the pelvis with total symmetry.

"II" Position - folded hind legs (HAN u. HURD, 1994)

"II" Position - folded hind legs